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United States Patent |
5,110,070
|
Hagenlocher
,   et al.
|
May 5, 1992
|
Rigid airship having ribs and long beams forming a carrier frame
Abstract
A rigid airship has a carrier frame with trianguar cross-ribs
interconnected by longitudinal beams, one connectd to each corner of the
triangle. Thus, prism-type frame sections are formed which are stiffened
by diagonal tensioning members (D). The prism of each frame section (A)
has two lateral sides and a base side. Each of the three sides is
stiffened with two diagonal tensioning members. Junctions between
neighboring frame sections are formed at the triangle corners. Carrier gas
cells, the skin of which forms at least part of the airship skin, are
secured in the frame sections. The base of each triangle cross-rib forms
the base of the frame. One or more air chambers are formed in the belly of
the airship below the base of the frame.
Inventors:
|
Hagenlocher; Klaus (Friedrichshafen, DE);
Windischbauer; Florian (Lindau, DE)
|
Assignee:
|
Luftschiffbau Zeppelin GmbH (Friedrichshafen, DE)
|
Appl. No.:
|
712269 |
Filed:
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June 7, 1991 |
Foreign Application Priority Data
Current U.S. Class: |
244/125; 244/30 |
Intern'l Class: |
B64B 001/06 |
Field of Search: |
244/125,126,128,131,24,25,30
|
References Cited
U.S. Patent Documents
1007405 | Oct., 1911 | Wagner et al. | 244/125.
|
1191077 | Jul., 1916 | Hermanson | 244/125.
|
1648935 | Nov., 1927 | Campau | 244/125.
|
2083051 | Jun., 1937 | Chapas | 244/125.
|
Foreign Patent Documents |
224322 | Jun., 1909 | DE2.
| |
241365 | Sep., 1910 | DE2.
| |
314846 | Nov., 1912 | DE2.
| |
303909 | May., 1922 | DE2.
| |
405563 | Nov., 1924 | DE2.
| |
462697 | Jun., 1928 | DE2.
| |
475985 | Apr., 1929 | DE2.
| |
520664 | Feb., 1931 | DE2.
| |
610976 | Feb., 1935 | DE2.
| |
657909 | Mar., 1938 | DE2.
| |
1531350 | Feb., 1970 | DE.
| |
1781416 | Apr., 1972 | DE.
| |
509501 | Nov., 1920 | FR.
| |
49829 | Nov., 1909 | CH.
| |
123604 | Mar., 1919 | GB.
| |
211334 | Feb., 1924 | GB.
| |
Other References
"Vergleichende Strukturuntersuchungen an Luftschiffmodellen" p. 161 etc. of
convention Flugsysteme leichter als Luft of Mar. 1976. The article is by
Institut fuer Statik und Dynamic der Luft-und Raumfahrtkonstruktionen an
der Univ Stuttgart.
The above reference has been adequately discussed in the specification.
Article entitled: "AD-500: the commercial airship"; pp. 539-544, Flight
Internationa., Feb. 24, 1979.
Translations of the Foreign Language Documents are not Readily Available.
|
Primary Examiner: Peters, Jr.; Joseph F.
Assistant Examiner: Mojica; Virna Lissi
Attorney, Agent or Firm: Fasse; W. G.
Claims
What is claimed is:
1. A rigid airship comprising a carrier frame including longitudinal beams
and a plurality of triangular cross-ribs each having a base arranged
horizontally in a lower option of said carrier frame, means forming
junctions between said triangular cross-ribs and said longitudinal beams
at corners of said cross-ribs to form quadrangular frame components each
comrpisnig two cross-ribs and two longitudinal beams interconnecting said
two cross-ribs, thereby enclosing quadrangular surfaces, diagonally
extending tension elements in said quadrangular frame components, whereby
three of said quadrangular frame components form a longitudinal frame
section lift gas cell means arranged in said longitudinal frame sections
between triangular cross-ribs, each lift gas cell means bearing with an
outer portion against an inner surface of the respective longitudinal
beams to which said lift gas cell means is secured, each lift gas cell
means having a cell skin projecting laterally from the cross-ribs and from
the longitudinal carrier beams so that said lift gas cell means form with
their cell skin an outer skin of said rigid airship over the length of the
respective longitudinal frame section, said lift gas cell means having a
lower portion loosely resting on said tension elements diagonally crossing
said quadrangular surface formed by two lower base longitudinal beams and
two triangular bases, whereby a lower portion of the respective lift gas
cell mean forms a separation wall between gas in said lift gas cell means
and at least one air chamber formed in a lower belly portion of said
airship, and a separate envelope portion arranged between said base
longitudinal beams to downwardly close said at least one air chamber,
whereby said envelope portion completely encloses the surface of said
lower belly portion of said airship while said cell skin of said lift gas
cell means enclosed the remaining surface of said airship.
2. The airship of claim 1, comprising a three component control tail unit
including fins secured to ends of three longitudinal beams.
3. The airship of claim 1, wherein said cross-ribs are constructed as
isoceles triangles having a base facing down and a tip formed by triangle
sides of equal length, facing up.
4. The airship of claim 1, wherein said cross-ribs and said longitudinal
beams are constructed as a trusswork.
5. The airship of claim 4, wherein said longitudinal beams forming part of
said trusswork comprise a straight inner flange and a curved outer flange,
said curved outer flange having a curvature corresponding to an outer
longitudinal contour of the airship.
6. The airship of claim 1, further comprising propulsion engines and means
for mounting said propulsion engines to junction points of the base of
said carrier frame.
7. The airship according to claim 6, further comprising mounting means for
tiltably mounting said engine to said junction point or points.
8. The airship according to claim 1, further comprising a tail engine
secured to a tail end of said airship.
9. The airship of claim 1, further comprising anchoring connectors secured
to junction points of the base of said carrier frame.
10. The airship of claim 1, wherein said tensioning elements in the
longitudinal frame sections pass through the wall of said lift gas cell
means arranged in the respective frame section in a gas-tight manner, and
further comprising tensioning means for connecting said tensioning
elements, said tensioning means being arranged in an air space of said
junctions of said carrier frame.
11. The airship of claim 10, wherein a gas-tight bellows is arranged at a
point where said tensioning elements pass through said cell skin of said
lift gas cell means.
12. The airship of claim 1, wherein a lower skin portion of said lift gas
cell means forming a separation wall between lift gas in said lift gas
cell means and said at least one air chamber form sack-type bulges which
hang downwardly between said tensioning members into said at least one air
chamber.
13. The airship of claim 1, comprising a common air chamber for a plurality
of lift gas cell means arranged in sequentially positioned carrier frame
sections.
14. The airship of claim 1, further comprising means (V, V') for
controlling an air excess pressure required in said at least one air
chamber.
15. The airship of claim 1, wherein intermediate spaces between two lift
gas cells of said lift gas cell means, which are separated by said
cross-ribs, are in communication with said at least one air chamber.
16. The airship of claim 15, further comprising cover strips
interconnecting two lift gas cells of said lift gas cell means which are
separated from each other by a cross-rib between two frame sections, said
cover strips sealing said intermediate space and fully closing the outer
skin of the airship in an airtight manner.
17. The airship of claim 1, wherein an apex space in which an upper
longitudinal carrier beam of the carrier frame is arranged and which is
covered on its sides by an outer skin of the airship, is further covered
by an additional strip.
18. The airship of claim 1, wherein a groove formed by said lift gas cell
means for holding a longitudinal beam member is covered by border strips
of said air chamber envelope portion.
19. The airship of claim 1, further comprising a gondola and means for
suspending said gondola from a base portion of said carrier frame so that
said gondola can move into said chamber in response to an impact.
20. The airship of claim 19, wherein said means for suspending comprise
damping members for damping an impact.
Description
THE INVENTION
The invention relates to a rigid airship with a carrier frame formed of
cross-ribs interconnected by long beams. A plurality of cross-ribs is
interconnected by long beam sections interposed between neighboring
cross-ribs. The so-formed carrier frame supports the lift producing
carrier or lift gas cells and any other structural groups needed for the
operation of the airship.
BACKGROUND INFORMATION
Airships of this type are referred to as rigid airships in contrast to
so-called nonrigid or pressure airships. The pressure airships have only a
single carrier gas cell and do not require a carrier frame. Advances made
in the aircraft construction lead to the transport of passengers and goods
primarily by aircraft in recent decades. However, there are special fields
where the high transport speed of aircrafts is not especially important so
that airships could be advantageously used in these special fields. It is,
for example, advantageous when an aircraft is capable of cruising for
prolonged periods of time in the vicinity of its destination at very low
speeds, or even better, if it is capable to remain in a floating or
rather, hovering, state for a longer period of time in a fixed location.
Incidentally, in this context the term "aircraft" is intended to include
airships. Airships are well capable of satisfying these requirements.
Thus, repeated investigations have been made with regard to the use of
airships. In actual practice, frequently the above mentioned pressure
airships, also known as blimps, have been used. These blimps are somewhat
smaller in volume and less expensive than conventional rigid airships. Due
to avoiding a carrier frame, the blimps are not only lighter, but
correspondingly less complicated in their construction and hence less
expensive in their manufacture. Another advantage of blimps is the fact
that even if they are relatively small, they still can carry a
satisfactory payload. However, it is a disadvantage of blimps that their
travel speed is rather low due to their plump shape. Another disadvantage
is seen in that blimps are not very stable on their course and there is
always the problem of gas leakage. When a blimp loses pressure, it is no
longer effectively steerable.
Conventional rigid airships normally comprise a carrier frame made of a
substantial number of ring-type cross ribs interconnected at junction
points by a plurality of longitudinal beams. The ring-type cross-ribs are
constructed as polygons comprising, for example, more than twenty
cross-rib sections, whereby for satisfying strength requirements each
corner of such a polygonal rib is connected with each other corner of the
same ring-type rib by tension wires. At the corners of the ring-type ribs
junction points are provided for the connection of the mentioned
longitudinal beams. These junction points constitute the connection
between any given ring to its neighboring rings. The so constructed
multi-cornered sections of the carrier frame support the gas cells within
the framework. The outer surface of the framework is closed by the
so-called outer skin. The lift producing gas cells are held in place
inside the framework by netting so that the lift gas cells bear against
the inner surfaces of the frame members, whereby an intermediate space is
formed between the skin of the individual gas cells and the outer skin of
the airship. The frame members are arranged in this intermediate spacing
which is lost for producing lift.
The individual cross rib sections of the rib rings and the longitudinal
beams are conventionally constructed as a truss or framework. Such a
construction involves a substantial technical effort and expense for the
formation of the carrier frame. Another disadvantage of a truss-type
carrier frame is seen in that it is sensitive against localized force
introduction and against vibrations. Thus, even minor accidents may lead
to substantial damage of the carrier frame structure which in turn entails
a substantial effort and expense for maintenance and repair work. It
should also be mentioned in this context that due to the weight of the
carrier frame only relatively large rigid airships having a lift volume of
several ten thousandths cubic meters, provide a satisfactory payload.
However, airships of such sizes are not desirable for many purposes.
The above mentioned drawbacks of rigid airships must be contrasted to a few
advantageous characteristics of such rigid airships. For example, due to
the aerodynamically advantageous outer contour of rigid airships, they
have a higher operational speed and a good course stability as compared to
blimps. Another important advantage of rigid airships is their larger
safety due to the use of a plurality of gas cells and due to the fact that
gas loss is usually limited to one or only a few gas cells. Further, the
rigid airship retains its contour and hence remains completely steerable.
A report entitled: "Flight Systems Lighter Than Air", published in March
1976 by the DGLR-Committe 2A6 contains a section entitled: Comparative
Structural Investigations of Airship Models, by the "institute for Static
and Dynamic Air-and Spacecraft Constructions" of the University of
Stuttgart, Federal Republic of Germany. The committee investigates the
construction of a carrier frame for airships. The suggestion made in these
investigations differentiaties itself from previous rigid airship
constructions in that substantially all cross-components of the structure
have been obviated. The cross-components have been replaced by a
pretensioned, compression loaded outer skin. This type of construction as
proposed by said committee provides sustantial weight savings as compared
to previous rigid airships while permitting the same structural loading of
the carrier frame. The omission of heavy cross-ribs also substantially
simplifies the manufacturating operations.
The report refers to carrier frame structures that have been investigated
in which instead of the cross-ribs, three beams are provided in the shape
of a triangle standing on its tip. The outer skin of the airship is
wrapped externally around the three carriers. Longitudinal carrier beam
structures are connected to the corners of the three cross carriers. The
longitudinal carrier beam constructions interconnect the cross-carrier
ribs with each other in sections and sequentially. However, the
longitudinal carrier members secured to the lower tip of the triangle are
sensitive to damage. Structural details regarding the carrier gas cells
and any other structural features of the airship are not provided in said
report. The report merely shows that by a simplified triangular
construction of the ribs of the carrier frame weight savings are possible.
OBJECTS OF THE INVENTION
In view of the foregoing it is the aim of the invention to achieve the
following objects singly or in combination:
to construct an airship that combines the undeniable advantages of the
rigid airship with those of the blimp, while simultaneously avoiding the
disadvantages of both;
to construct a rigid airship that has an optimally light carrier frame and
a high payload as well as a substantial strength;
to provide a rigid airship that can be manufactured by simpler means and
hence requires a smaller technical effort and expense than was necessary
heretofore; and
to provide relatively small rigid airships at relatively low manufacturing
costs, whereby the skin of the carrier gas cells shall also form the
envelope or skin of the airship or most of that envelope.
SUMMARY OF THE INVENTION
The above objects have been achieved according to the invention in a rigid
airship that is characterized by the following features. The base of the
triangular cross-ribs is arranged horizontally in a lower portion of the
carrier frame of the airship. The longitudinal frame sections are formed
by quadrangular frame components, each comprising two cross-carrier
members of neighboring cross-carrier triangles and two longitudinal beams
interconnecting the cross-carrier members, thereby enclosing quadrangular
surfaces. These quadrangular surfaces are strengthened by two diagonally
extending tensioning elements. A lift gas cell is arranged int eh
longitudinal frame sections. Each lift gas cell bears with its upper
portion against the inner surface of the longitudinal carrier beam to
which it is secured. Each lift gas cell projects laterally from the
cross-carrier ribs and the longitudinal carrier beams so that these cells
form with their cell skin over the length of the respective longitudinal
frame section, the envelope of the lift gas cell and the outer skin of the
airship. The lower portion of the lift gas cell loosely rests on the
tension elements diagonally crossing the quadrangular surface formed by
the two lower base longitudinal carrier beams, whereby the lower portion
of the respective lift gas cell forms a separation wall between the gas in
the lift or carrier gas cell and an air chamber provided in the lower
portion of the airship. A separate envelope is arranged between the base
longitudinal carriers to downwardly close said air chamber, whereby the
envelope completes or supplements the cross-sectional configuration of the
airship.
The just described structure of the carrier frame according to the
invention makes it possible to secure three components of a tail unit to
the ends of the the three longitudinal carrier beams. It is further
possible in the present structure that the propulsion plants which are
secured tot he two lower longitudinal carrier beams, can be positioned
within a substantially freely selectable range since the anchoring
connectors may be secured to the junction points of the carrier frame.
Another advantage of the invention is seen in that the construction of the
triangular shaped cross-carriers or cross-ribs in combination with the
longitudinal carrier beams require few simple structural components,
whereby manufacturing costs are lowered to an optimal extent. Individual
components such as the longitudinal or cross-beams may be conveniently
premanufactured and then separately assembled. The entire ship has a low
total weight, whereby a high payload and hence efficiency is achieved. Due
to the diagonal tensioning of the quadrangular fields or surfaces, the
present carrier frame has a high stiffness. As mentioned, the quadrangular
surfaces are defined by the longitudinal sections of the carrier beam
arranged between neighboring cross-beams formed as triangles, the base of
which faces down. The stable and elongated aerodynamically advantageous
shape of the carrier frame makes it possible to secure all structural
components to the carrier frame, such components including propulsion
plants, control surfaces, gondolas, and so forth.
Stress is released from the trusswork of the carrier frame by the internal
pressure to which the outer skin is exposed. This feature additionally
improves the strength characteristics of the airship according to the
invention, especially with regard to the buckling strength, the bending
strength, and the torsion strength. By arranging an air chamber in the
lower portion or section of the airship body it is possible to place the
base of the carrier frame into an inner portion of the outer skin, whereby
protection against damage is provided. For example, when a hard landing is
made the gondola can move into the air chamber in an elastic manner before
carrier frame components can cause damage to persons in the gondola.
The carrier or lift gas cells are secured in the longitudinal direction of
the airship to the outer beams extending in parallel to each other and
forming the longitudinal beam members of the carrier frame. The beams
themselves are advantageously formed as a trusswork. The outer flange or
chord of such trusswork members may be curved in the individual sections
of the framework, whereby the curvature corresponds to the outer
longitudinal vaulting of the airship. Since the outer skin of the lift gas
cells which are arranged in a row in the longitudinal direction also forms
the outer envelope of the airship, and since a separate airship envelope
outside the carrier construction is not provided at a spacing from the
carrier gas cells, the entire airship volume is optimally utilized for
containing the lift producing gas volume. It has been found that the gain
in lift is about 6% compared to a conventional rigid airship of the same
size or volume.
The carrier or lift gas cells contribute to the stiffening of the carrier
frame due to the internal pressure inside these gas cells. Even if there
should be a pressure loss, the airship retains its configuration and hence
remains fully steerable by the control surfaces of the tail unit. Another
advantage is seen in that due to the circular outer configuration of the
carrier gas cells in the area of the base longitudinal carriers, the
airship retains a circular cross-section and the conventional polygonal
cross-sectional shape is avoided.
Due to the cooperation of the carrier frame according to the invention with
the construction of the carrier gas cells according to the invention, the
disadvantages mentioned above with regard to the prior art have been
avoided while obtaining for a relatively small airship volume the
advantageous characteristics of a larger rigid airship.
BRIEF DESCRIPTION OF THE DRAWINGS
In order that the invention may be clearly understood, it will now be
described, by way of example, with reference to the accompanying drawings,
wherein:
FIG. 1 shows a perspective view of an airship according to the invention,
whereby the outer skin or envelope has been partially removed to reveal
the frame structure according to the invention;
FIG. 2a is a side view onto the tail unit shown in FIG. 1;
FIG. 2b is a sectional view along the section line D--D in FIG. 2A;
FIG. 2c shows a trusswork detail viewed in a direction perpendicularly and
horizontally to the longitudinal axis of the airship;
FIG. 2d is a sectional view perpendicularly to the longitudinal airship
axis in a plane passing through the airship upstream of the propulsion
engines;
FIG. 3 illustrates a perspective view of one longitudinal section of the
carrier frame partially in section;
FIG. 4a is a sectional view perpendicularly through the longitudinal
airship axis;
FIG. 4b is a sectional view along section line C--C in FIG. 4a;
FIG. 5a shows, on an enlarged scale, the detail in the circle Va in FIG.
4a;
FIG. 5b shows, on an enlarged scale, the detail Vb in FIG. 4b;
FIG. 6a shows a perspective view of a junction construction between tubular
frame members;
FIG. 6b shows a junction construction between truss-type frame members,
whereby the view extends in the direction of the longitudinal airship
axis;
FIG. 6c shows the junction construction of FIG. 6b, however in a plan view
6c-6c omitting the upwardly directed frame member of the triangular rib;
of a longitudinal frame member
FIG. 7a shows a side view of a longitudinal frame member constructed as a
truss member;
FIG. 7b is a sectional view along section plane E--E in FIG. 7a;
FIG. 7c is a sectional view along section plane F--F in FIG. 7a;
FIG. 8a is a schematic side view of an airship according to the invention
showing the normal position of the propulsion engines and the gondola;
FIG. 8b is a sectional view along section line A--A in FIG. 8a;
FIG. 8c is a view similar to that of FIG. 8a showing an emergency position
of the gondola partly elastically recessed into the air space of the
airship;
FIG. 8d is a sectional view along section line B--B in FIG. 8a showing the
gondola in its normal position;
FIG. 8e is a view similar to FIG. 8d, but showing the gondola in its
recessed emergency position;
FIG. 9a is a sectional view perpendicularly through the longitudinal
airship axis to illustrate the mounting of an engine; and
FIG. 9b is a sectional view along section line 9b-9b in FIG. 9a.
DETAILED DESCRIPTION OF PREFERRED EXAMPLE EMBODIMENTS AND OF THE BEST MODE
OF THE INVENTION
The perspective view of FIG. 1 showing an airship according to the
invention, illustrates the assembly of the entire rigid carrier frame
using triangle ribs and longitudinal beams to form frame sections A. In
the central portion of FIG. 1, the outer skin or envelope has been removed
to illustrate the internal structure and arrangement of the carrier frame.
The cross-ribs of the frame are constructed as triangular cross-beams
having preferably the shape of an isosceles triangle. Each triangular
cross-beam has two equal sides and a base facing down. The first
cross-beam visible in FIG. 1 has two equal sides S11 and S12 and a base
S13. The axially spaced next triangle has two equal sides S21 and S22 and
a base S23. The two neighboring triangular cross-beams just described are
spaced from each other by the axial length of a frame section A. The tips
of the triangular cross-beams point upwardly. The basis of all triangles,
namely S13, S23 and so forth, extend horizontally and form the lower base
of the carrier frame. To form a frame section A two neighboring triangular
cross-beams are interconnected by longitudinal beams L1, L2, and L3
interconnecting respective corners of the two neighboring triangular
beams. As a result, each frame section has a prismatic shape with three
quadrangular surfaces, one of which faces downwardly forming the base of
the carrier frame and the two other surfaces slant laterally downwardly to
form the sloping side surfaces of the prism. The base surface in a front
section of the airship is, for example, bounded by the base beam member
S13 and S23, and by the longitudinal beam members L1 and L3. A lateral
surface of the prism is, for example, bounded by the beam members S12 and
S22, as well as L2 and L3. As is shown in the drawing, the just mentioned
plane quadrangular surfaces are the location of reinforcing tension wires
or elements D extending diagonally from corner to corner. These diagonal
tension elements D may be flexible and can, for example, be formed by
tension wires or cables cooperating with an adjusting mechanism, for
example, a turnbuckle 8 forming a connector. The double diagonal
tensioning improves substantially the strength of the carrier frame and
constitutes an advantageous developement compared to the above mentioned
conventional triangular cross-ribs with their tips pointing down. Viewing
several longitudinal frame sections A in conjunction, it is clear from
FIG. 1 how the longitudinal carrier frame is constructed with the
longitudinal beam members L1, L2, L3 interconnecting the triangular ribs.
By interconnecting the longitudinal beam members in series with one
another continuous longitudinal beams are formed. The base of the carrier
frame formed by the longitudinal beam members L1, L3 are ideally suited
for supporting components of the airship, such as the propulsion engines.
Especially the junction points where the longitudinal beam members are
joined to the cross-beam members are suitable for the mounting of the
engines. The control tail unit F and the suspension of the gondola G will
be described in more detail below.
FIGS. 2a and 2b show a simplified illustration of the tail section of an
airship according to the invention, whereby FIG. 2b is a sectional view
along section line D--D in FIG. 2a. The fins F1, F2, and F3 of the control
tail unit are advantageously secured to the rear ends of the three
longitudinal carrier beams L1, L2, and L3. This three component tail unit
with its fins F1, F2, and F3 has an inverted Y-configuration. FIG. 2a
shows a separate tail engine H including a jet deflector H1. By deflecting
the jet more or less downwardly or, if necessary, also to one side or the
other, more or less, an advantageous additional control of the airship is
provided during hovering flight. This additional jet directional control
efficiently supplements the aerodynamic control provided by the fins and
rudder, especially during the mentioned hovering flight when the rudder is
not very effective due to the low hovering speed. FIG. 2b also indicates
two triangular cross-ribs Q as well as the external skin or envelope 1 of
the airship having a circular cross-section.
FIG. 2c shows two neighboring cross-ribs or cross-beams with the respective
cross-beam members S12 and S22 interconnected by longitudinal beam members
L2 and L3 forming a rectangular configuration. The location of the
diagonal tensioning members D is evident from FIG. 2C showing that the
tensioning members D are positioned in one lateral surface of each prism.
An engine T is mounted to the junction point formed by the beam members
S12, L3, and L3'. The double arrow AR indicates the tilting range of the
engine T.
FIG. 2d shows a cross-rib comprising the above mentioned rib members S11
and S12 forming isoceles sides of the triangle and the rib or cross-beam
member S13 forming the base. The longitudinal beam members L1, L2, and L3
extend perpendicularly to the plane of the drawing. A circle 1' indicates
the outer skin on envelope 1 or envelope of the airship. The skin 1
encloses the carrier gas cells 1'. Two engines T1 and T2 are mounted to
the junction points where the base member S13 of the triangle is joined to
the longitudinal beam members L1 and L3. It is important for the
construction of the cross-ribs as triangular beams, that the lateral beam
members S11 and S12 are triangle sides of equal length. Moreover, the
length of the base member S13 is less critical. However, it is
advantageous for a symmetrical construction that all three beam members
S11, S12 and S13 have the same length to form an equi-lateral triangle.
FIG. 3 shows one complete longitudinal section A in a perspective view as
part of the carrier frame of the airship. As mentioned, the first
cross-rib comprises the cross-beam members S11, S12, and S13 and the
second cross-beam comprises the beam members S21, S22, and S23. The
cross-beams extend in parallel to each other at a spacing determined by
the longitudinal beam members L1, L2, and L3 extending in parallel to the
central longitudinal axis of the airship while the triangular cross-beams
extend perpendicularly to the longitudinal ship axis.
A lift gas cell 1' has an upper portion with a circular cross-section
between the longitudinal beams L1 past the longitudinal beam L2 to the
other lower longitudinal beam L3. The skin of the lift gas cell 1' bears
against the inner surfaces of the three longitudinal beam members. Outside
the beam members, the skin of the gas cell 1' bulges outwardly to an
extent corresponding approximately to the respective radial dimension of
the beam members or even somewhat more so that the beam members L1, L2 are
located in a ditch or groove formed by the skin of the gas cell around the
beam members. A downwardly facing section of the lift gas cell 1' between
the longitudinal beam members L1 and L3 rests on the one hand on the
diagonal tensioning members D in the surface defined by the beam members
L1, L3, S13, and S23. In the surface areas outside the just mentioned
frame components and outside the diagonal tensioning members, the gas cell
may bulge downwardly with its lower skin section 2 as best seen in FIG. 3.
This lower wall section 2 separates the gas cell 1' from an air chamber K
arranged in the lift downwardly facing belly portion of the airship below
the carrier frame. The air chamber K is enclosed by a skin section 3
forming part of the skin of the airship. The remaining skin of the airship
is formed by the skin 1 of the gas cells except where the cross-ribs and
the longitudinal beam members are located which are covered by cover
strips, edges or tape. For this purpose, the edges 30 of the belly skin 3
are pulled up above the longitudinal beam members L1 and L3 to cover these
beam members in a gas-tight manner. In addition to the gas-tight
connection of the edges 30 to the skin 1 of the gas cells 1' to cover the
beams L1, L3, the edges 30 make sure that the longitudinal beam members
are completely enclosed. A cover tape or strip 4 covers the groove or
ditch in which the upper longitudinal beam member L2 is located. The strip
or tape 4 again must be connected in a gas-tight manner to the neighboring
skin areas 1 of the gas cells 1'. Further details of the cover tape 4 will
be described below. One carrier gas cell 1' is arranged between
neighboring cross-ribs. Specifically, one cell 1' is located between the
cross-beam members S11, S12, and S13 on the one hand and the cross-beam
members S21, S22, S23 on the other hand. The next gas cell is located
between the beam members S21, S22, and S23 on the one hand and the next
following triangle in the frame structure. Thus, two neighboring carrier
gas cells are separated from each other by a triangular cross-beam,
whereby the cross-beam is located in the space Z which communicates with
the air chamber K. The intermediate space Z is also covered in a gas-tight
manner by tapes similar to the cover tape 4 and to the edges 30. The
circumferential tape may extend entirely around the airship so as to cover
any seams between neighboring skin sections 3 which cover the airship's
belly.
FIG. 4a shows a simplified cross-section passing through a triangular
cross-beam, thus illustrating the location of the cross-beam members S11,
S12, and S13, as well as the longitudinal beam members L1, L2, and L3, the
dash-dotted lines in each of the cross-beam members S11, S12, and S13
indicate the position of the diagonal tensioning members D. The upper
portion of the gas-tight envelope 1 of the carrier gas cell 1' which is
shown behind the triangular cross-beam forms a circular configuration as
mentioned above. The cross-section illustrates especially the bulging of
the carrier gas cell skin around the longitudinal carrier beam members L1,
L2, and L3. In other words, the gas cell bulges on both sides of the
longitudinal beam members so that the resulting groove provides space for
the longitudinal beam. The cover strip 4 is, for example, adhesively
bonded to the skin 1 of the air cells as is shown in more detail in FIG.
5a showing, on an enlarged scale, that portion of FIG. 4a encircled by a
dash-dotted line Va. The above mentioned air chamber K is located below
the base cross-beam member S13, and the downwardly facing wall 2 also
bulges downwardly outside the base beam member S13 as indicated at 2. The
air filling in the air chamber K is indicated by dots.
FIG. 4b illustrates, on a somewhat enlarged scale compared to FIG. 4a, a
sectional view along section line C--C in FIG. 4a to show the diagonal
tensioning members D. The downwardly facing skin 2 of the carrier or lift
gas cells 1' form sacks 20 that bulge through the spaces between the
tensioning members D facing downwardly, whereby these sacks penetrate into
the air chamber K. The cooperation of the carrier gas cells 1' with the
air chambers K is conventional and hence will not be described in more
detail in conjunction with the present invention. The downwardly bulging
sacks 20 will penetrate deeper into the air chamber K as shown by
dash-dotted lines in FIG. 4b when there is a low air pressure in the
chambers K. FIG. 4b also illustrates the disk type intermediate spaces Z
between two neighboring gas carrier or lift cells 1'. The cross-beam
members S11 and S21 are located in these intermediate spaces Z. Although
the downwardly facing skin or envelope portion 2 of the carrier gas cells
1' bulge downwardly and rest on the lower diagonal tensioning members, the
lateral diagonal tensioning members penetrate through the walls, or rather
through the skin of the carrier gas cells 1' as will be described in more
detail below with reference to FIG. 5b. This penetration of the lateral
diagonal tensioning members D through the skin 1 of the carrier or lift
gas cell 1' is located near the connection of the carrier gas cell to the
longitudinal beam members.
FIG. 5a shows on an enlarged scale the portion encircled by a dash-dotted
line in FIG. 4a, whereby the cross-beam members S11 and S12 are shown
cut-off and the longitudinal beam member L2 extends perpendicularly to the
plane of the drawing. The longitudinal carrier beam member L2 rests in the
above mentioned ditch or groove 1" formed by a portion of the skin 1 of
the carrier gas cell 1'. The longitudinal carrier beam L2 is provided
along its entire length at its upwardly facing side with mounting flanges
25 projecting to both sides of the beam L2. The mounting flanges 25 in
turn are secured to skin extension edges 40 of the airship skin 1 which
may simultaneously be the outer skin of the carrier gas cells 1'. Lashing
elements 5 are interposed between the mounting flanges 25 and the skin
edges 40 to tightly lash the skin edges 40 to the flanges 25. A gas tight
cover tape or strip 4 is secured in a gas-tight manner to the edges 40,
for example by an adhesive 40'. Instead of an adhesive, a gas-tight seam
may be formed, for example, by sewing or welding or the like. Even a hook
and loop (Velcro.RTM.) may be sufficiently gas-tight. The cover tape or
strip 4 covers the ditch or groove formed by the skin portion 1" including
the skin edges 40 and the lashing elements 5. FIG. 5b shows on an enlarged
scale, portion Vb from FIG. 4b, whereby the longitudinal section of FIG.
5b does not pass exactly through the center of the longitudinal beam
member L2, but in front of it in order to show the junction construction
between the beam members S11 and L2 and also illustrating the connection
of the diagonal tensioning members D. A turnbuckle type connector 8
secures one end of the respective tensioning member D to a lug 8', whereby
the tensioning member can be individually tensioned by turning the
turnbuckle. A gas-tight nipple type connector 7 forms a gas-tight inlet
through the skin 1 of the respective carrier gas cell 1'. The connector 7
may, for example, be formed as an elastic bellows that permits the sliding
movement of the tensioning member D through the wall of the respective
carrier lift gas cell 1'. A further cover strip or tap 4' extends
circumferentially around the airship for closing the gap formed between
neighboring carrier gas cells 1' where the cross-ribs S11, S12, and S13
are located.
FIG. 6a illustrates in a simplified manner a junction coupling between two
longitudinal beam sections La and Lb with each other and with two
cross-beam members Sa and Sb, whereby all beam members are of tubular
construction. However, the frame members may also be of a truss
construction to be described below. A tubular coupling sleeve LS receives
axially the two longitudinal beam members La and Lb. The coupling sleeve
LS has two radially and axially extending outer flanges LS1 and LS2. The
cross-beam member Sa is secured to the flange LS1. The ends of the lateral
tensioning members D1 and D2 are also connected to the flange LS1. The
horizontally extending base cross-beam member Sb is connected to the
flange LS2. Similarly, the horizontally extending tensioning member D3 is
connected to the flange LS2. The fourth horizontal tensioning member is
not visible in FIG. 6a, because it is behind the cross-beam member Sa.
FIG. 6b illustrates a view partially in section, onto a junction point
between longitudinal and cross-frame members, each of which is made as a
truss construction. The outer cover tape or strip 30 which covers the
longitudinal beam member L1 is shown as a dashed line merging onto the
outer skin of the carrier gas cell 1', whereby the connection at 40' may
be the same as described above with reference to FIG. 5a. Each of the
carrier beams has a pointed end that merges into the junction point as
shown in FIG. 6b.
FIG. 6c shows a view in the direction of the section plane 6c-6c in FIG.
6b. The diagonal tensioning members D are again connected to the junction
point through a turnbuckle 8, for example, and through the gas-tight
connector 7 passing through the skin 1 of the respective carrier or lift
gas cell 1'.
FIG. 7a illustrates a truss construction for a longitudinal beam member L.
Each longitudinal truss member is constructed in accordance with the flow
dynamic requirements. For this purpose, the radially inner flange 9a of
the truss is straight, while the radially outer flange 9b of the truss is
curved so that it conforms to the respective outer curvature of the
airship at the particular location within the airship body where the
longitudinal beam member is used. FIGS. 7b and 7c show that along its
length the longitudinal beam member L1 has different radial heights H1,
H2.
FIG. 8a shows a schematic side view of an airship according to the
invention having, for example, a nose tip NT and nine longitudinal frame
sections A separated by eight cross-beams or cross-ribs Q1, Q2, Q3, Q4 and
so forth. A longitudinal section A is defined between two neighboring
cross-beams or ribs. Due to the described arrangement of the diagonal
tensioning elements D in combination with the triangular cross-ribs and
the longitudinal beam members at the three corners of the triangle, the
invention achieves a high strength frame structure to which the tail unit
with its fins F is secured as will be described in more detail below. A
tail propulsion engine H is secured to the very end of the tail for
steering purposes by means of a thrust vector produced by a jet of the
engine H. Along the belly and below the base B there are one or more air
chambers K. A gondola G is suspended by truss members or cables 15, 16
secured to the cross-beams or ribs Q1 to Q4. The suspension of the gondola
G may, for example, comprise damping members such as piston cylinder
devices or the like indicated at 17 in FIG. 8d.
FIG. 8b also shows the connection of the two engines T to the frame
structure at a junction point between the cross-rib Q4 and the respective
longitudinal beam members. Anchoring devices such as hooks and eyelets not
shown may also be connected to the carrier frame structure for securing
the airship on the ground.
FIG. 8a shows the gondola G in its normal position while FIG. 8c shows the
gondola after a hard landing, whereby the gondola G has moved elastically
into the space of the air chambers K. This elastically recessed position
of the gondola G in the air chamber K is also illustrated in FIG. 8e. This
feature of the invention greatly reduces damages to the gondola and injury
to persons.
With regard to the construction of the air chamber K it should be mentioned
that the air chamber can be subdivided in any suitable manner to form a
plurality of individual air chambers, but a single air chamber extending
along the entire length of the airship may be practical. However, a
plurality of air chambers, for example, corresponding to the number of
carrier or lift gas cells or a smaller number of air chambers may be
suitable. For example, one air chamber can be arranged below two carrier
or lift gas cells. In any event, each air chamber will be provided with a
venting valve V as shown in FIG. 8a. The venting valve V is an excess
pressure responsive valve and controls the air pressure within its air
chamber K in accordance with operational requirements. In FIG. 8a it is,
for example, assumed that the front section of the airship including the
cross-ribs Q1 to Q4 has a common air chamber K and that the rear section
of the airship has a separate second air chamber. The front air chamber is
equipped with its own ventilator or venting valve V' while the rear
section is provided with the ventilator or valve V. It is possible that
instead of the venting valves an air pressure device could be used for
assuring the required excess pressure in the air chambers.
FIGS. 9a and 9b show details of the mounting for an engine T to a junction
point formed between the members S of the cross-rib and the longitudinal
beam sections L. A pilon 18 is secured at one end to the junction point
and through a tiltable bearing 19 at the other end to a carrier member CM
connecting to the housing of the engine T which may, for example, be a
turbine driven propeller engine. With the aid of the tilting bearing 19 it
is possible to change the orientation of the longitudinal engine axis EA
relative to the longitudinal central axis of the airship so that the
engine jet is directed somewhat downwardly, please also see the tilting
arrow AR in FIG. 2c. FIG. 9b shows a sectional view approximately along
section plane 9b-9b in FIG. 9a, whereby the propeller P is tilted in a
position for forward movement. The propeller circle P' is seen in FIG. 9a.
Although the invention has been described with reference to specific
example embodiments, it will be appreciated that it is intended to cover
all modifications and equivalents within the scope of the appended claims.
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